Wifi virtual carrier sense for lte/wifi co-channel coordination

ABSTRACT

A wireless cellular device comprises physical layer circuitry configured to transmit and receive radio frequency electrical signals to communicate directly with one or more separate wireless devices using a communication channel of a cellular network and a WiFi communication channel of a WiFi communication spectrum; and processing circuitry configured to initiate transmission of a WiFi subframe via the WiFi communication channel to reserve communication time on the WiFi communication channel for use by the same or a different cellular device during the reserved communication time.

PRIORITY APPLICATION

This application claims the benefit of priority to U.S. ProvisionalApplication Ser. No. 61/909,938, filed Nov. 27, 2013, which isincorporated herein by reference in its entirety.

TECHNICAL FIELD

Embodiments pertain to transmitting packetized data using radio accessnetworks. Some embodiments relate to communicating cellular deviceinformation using a communication spectrum unlicensed to the type ofcellular device used to communicate the information.

BACKGROUND

Radio access networks are used for delivering one or more of datacommunications, voice communications, and video communications to userequipment such as a cellular telephone or a smart phone. Some radionetworks are packet switched networks and packetize information such asvoice and video data when it is sent over the network. As the demand forcommunicating voice and video increases, quality of service candeteriorate as the radio access networks approach their peak capacity.Thus, there are general needs for devices, systems and methods thatprovide a robust protocol for communication with user equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of a portion of an end-to-end networkarchitecture of an LTE network with various components of the network inaccordance with some embodiments;

FIG. 2 shows a flow diagram of an example of a method of operating awireless cellular device network in accordance with some embodiments;

FIG. 3 illustrates a functional block diagram of a wireless cellulardevice in accordance with some embodiments in accordance with someembodiments;

FIG. 4 illustrates a simplified example of operating a cellular deviceto reserve time on a WiFi communication channel in accordance with someembodiments;

FIG. 5 shows a timing diagram of an example of a message sent by acellular device to reserve time on a WiFi communication channel inaccordance with some embodiments; and

FIG. 6 shows a timing diagram of another example of a message sent by acellular device to reserve time on a WiFi communication channel inaccordance with some embodiments;

FIG. 7 shows a timing diagram of yet another example of a message sentby a cellular device to reserve time on a WiFi communication channel inaccordance with some embodiments.

DETAILED DESCRIPTION

The following description and the drawings sufficiently illustratespecific embodiments to enable those skilled in the art to practicethem. Other embodiments may incorporate structural, logical, electrical,process, and other changes. Portions and features of some embodimentsmay be included in, or substituted for, those of other embodiments.Embodiments set forth in the claims encompass all available equivalentsof those claims.

FIG. 1 shows an example of a portion of an end-to-end networkarchitecture of a long term evolution (LTE) network with variouscomponents of the network in accordance with some embodiments. Thenetwork 100 comprises a radio access network (RAN) (e.g., as depicted,the E-UTRAN or evolved universal terrestrial radio access network) 101and the core network 120 (e.g., shown as an evolved packet core (EPC))coupled together through an S1 interface 115. For convenience andbrevity, only a portion of the core network 120, as well as the RAN 101,is shown in the example.

The core network 120 includes mobility management entity (MME) 122,serving gateway (serving GW) 124, and packet data network gateway (PDNGW) 126. The RAN includes enhanced node B's (eNBs) 104 (which mayoperate as base stations) for communicating with user equipment (UE)102. The eNBs 104 may include macro eNBs and low power (LP) eNBs.

The MME 122 is similar in function to the control plane of legacyServing GPRS Support Nodes (SGSN). The MME manages mobility aspects inaccess such as gateway selection and tracking area list management. Theserving GW 124 terminates the interface toward the RAN 101, and routesdata packets between the RAN 101 and the core network 120. In addition,it may be a local mobility anchor point for inter-eNB handovers and alsomay provide an anchor for inter-3GPP mobility. Other responsibilitiesmay include lawful intercept, charging, and some policy enforcement. Theserving GW 124 and the MME 122 may be implemented in one physical nodeor separate physical nodes. The PDN GW 126 terminates an SGi interfacetoward the packet data network (PDN). The PDN GW 126 routes data packetsbetween the EPC 120 and the external PDN, and may be a key node forpolicy enforcement and charging data collection. It may also provide ananchor point for mobility with non-LTE accesses. The external PDN can beany kind of IP network, as well as an IP Multimedia Subsystem (IMS)domain. The PDN GW 126 and the serving GW 124 may be implemented in onephysical node or separated physical nodes.

The eNBs 104 (macro and micro) terminate the air interface protocol andmay be the first point of contact for a UE 102. In some embodiments, aneNB 104 may fulfill various logical functions for the RAN 101 includingbut not limited to RNC (radio network controller functions) such asradio bearer management, uplink and downlink dynamic radio resourcemanagement and data packet scheduling, and mobility management. Inaccordance with embodiments, UEs 102 may be configured to communicateOFDM communication signals with an eNB 104 over a multicarriercommunication channel in accordance with an OFDMA communicationtechnique. The OFDM signals may comprise a plurality of orthogonalsubcarriers.

The S1 interface 115 is the interface that separates the RAN 101 and theEPC 120. It is split into two parts: the S1-U, which carries trafficdata between the eNBs 104 and the serving GW 124, and the S1-MME, whichis a signaling interface between the eNBs 104 and the MME 122. The X2interface is the interface between eNBs 104. The X2 interface comprisestwo parts, the X2-C and X2-U. The X2-C is the control plane interfacebetween the eNBs 104, while the X2-U is the user plane interface betweenthe eNBs 104.

With cellular networks, LP cells are typically used to extend coverageto indoor areas where outdoor signals do not reach well, or to addnetwork capacity in areas with very dense phone usage, such as trainstations. As used herein, the term low power (LP) eNB refers to anysuitable relatively low power eNB for implementing a narrower cell(narrower than a macro cell) such as a femtocell, a picocell, or amicrocell. Femtocell eNBs are typically provided by a mobile networkoperator to its residential or enterprise customers. A femtocell istypically the size of a residential gateway or smaller and generallyconnects to the user's broadband line. Once plugged in, the femtocellconnects to the mobile operator's mobile network and provides extracoverage in a range of typically 30 to 50 meters for residentialfemtocells. Thus, a LP eNB might be a femtocell eNB since it is coupledthrough the PDN GW 126. Similarly, a picocell is a wirelesscommunication system typically covering a small area, such asin-building (offices, shopping malls, train stations, etc.), or morerecently in-aircraft. A picocell eNB can generally connect through theX2 link to another eNB such as a macro eNB through its base stationcontroller (BSC) functionality. Thus, LP eNB may be implemented with apicocell eNB since it is coupled to a macro eNB via an X2 interface.Picocell eNBs or other LP eNBs may incorporate some or all functionalityof a macro eNB. In some cases, this may be referred to as an accesspoint base station or enterprise femtocell.

In some embodiments, a downlink resource grid may be used for downlinktransmissions from an eNB to a UE. The grid may be a time-frequencygrid, called a resource grid, which is the physical resource in thedownlink in each slot. Such a time-frequency plane representation is acommon practice for OFDM systems, which makes it intuitive for radioresource allocation. Each column and each row of the resource gridcorrespond to one OFDM symbol and one OFDM subcarrier, respectively. Theduration of the resource grid in the time domain corresponds to one slotin a radio frame. The smallest time-frequency unit in a resource grid isdenoted as a resource element. Each resource grid comprises a number ofresource blocks, which describe the mapping of certain physical channelsto resource elements. Each resource block comprises a collection ofresource elements and in the frequency domain; this represents thesmallest quanta of resources that currently can be allocated. There areseveral different physical downlink channels that are conveyed usingsuch resource blocks. Two of these physical downlink channels are thephysical downlink shared channel and the physical down link controlchannel.

The physical downlink shared channel (PDSCH) carries user data andhigher-layer signaling to a UE 102 (FIG. 1). The physical downlinkcontrol channel (PDCCH) carries information about the transport formatand resource allocations related to the PDSCH channel, among otherthings. It also informs the UE about the transport format, resourceallocation, and H-ARQ information related to the uplink shared channel.Typically, downlink scheduling (assigning control and shared channelresource blocks to UEs within a cell) is performed at the eNB based onchannel quality information fed back from the UEs to the eNB, and thenthe downlink resource assignment information is sent to a UE on thecontrol channel (PDCCH) used for (assigned to) the UE.

As explained previously, the demand for communicating one or both ofvoice data and video data continues to increase. A RAN 101 mayexperience heavy communication traffic which can lead to adverse networkeffects such as communication latency for example. As shown in FIG. 1, aRAN can include UE devices and eNB devices such as LP eNBs and/or macroeNBs. To alleviate network traffic, network capacity can be added byproviding communication capability to the RAN devices from networks thatoperate using a communication spectrum not licensed for use by thecellular network devices. Communication peaks may occur locally and theRAN serving the locality may experience peak demand. The locality mayinclude a WiFi network for computing devices such as laptop computersand computer tablets, but the wireless cellular devices are not licensedto operate in the WiFi communication spectrum (e.g., communicationchannels of 2.4 gigahertz (GHz) or 5 GHz). According to someembodiments, the wireless cellular devices of a RAN reservecommunication time on the WiFi communication channel and communicateinformation using the WiFi communication spectrum.

FIG. 2 shows a flow diagram of an example of a method 200 of operating awireless cellular device network. The cellular device network mayinclude one or more eNBs and UEs. The cellular device network may be,among other things, an LTE cellular network, an LTE-Advanced cellularnetwork, or a fifth generation (5G) LTE cellular network. To mitigatepossible interference to WiFi devices caused by the cellular devicetransmissions on WiFi channels, the cellular devices use a timereserving message to inform the WiFi devices of transmissions by one ormore cellular devices. This reduces the amount of collisions betweendevices that may otherwise occur, and promotes an acceptable level ofuse of WiFi communication channels by both the cellular devices and theWiFi devices. It also provides for lower-overhead communication amongmultiple cellular devices through the central scheduling of one or bothof cellular downlink and uplink transmissions.

At block 205, a WiFi subframe is transmitted via a WiFi communicationchannel of a WiFi communication spectrum using a cellular device. TheWiFi communication channel may be established by a WiFi networkimplemented under one of the Institute of Electrical and ElectronicEngineers 802.11 standards, such as the IEEE 802.11-2012 standardpublished Mar. 29, 2012.

The WiFi subframe may include a message that reserves communication timeon the WiFi communication channel. The WiFi subframe may be included ina WiFi frame or a cellular network frame. Any WiFi device monitoring theWiFi communication channel that is capable of decoding the message willconsider the channel unavailable and will defer any transmission and maydefer countdown of its contention window until after the duration of thereserved time has elapsed.

At block 210, the reserved time is used by a cellular device tocommunicate information with another cellular device via the WiFicommunication channel. The reserved time can be used by the cellulardevice that transmitted the message or can be used by a separatecellular device. The reserved time can be used for communication betweena cellular network node device (e.g., an eNB) and a cellular UE device(e.g., a smart phone), between two UE devices, or between two networknode devices.

FIG. 3 illustrates a functional block diagram of a wireless cellulardevice in accordance with some embodiments. The cellular device 300 maybe any of the UEs 102 illustrated in FIG. 1, or the cellular device maybe any of the eNBs 104 of FIG. 1. The cellular device 300 may includephysical layer (PHY) circuitry 302 for transmitting and receiving radiofrequency electrical signals using one or more antennas 301 electricallyconnected to the PHY circuitry. The PHY circuitry 302 may includecircuitry for modulation/demodulation, upconversion/downconversion,filtering, amplification, etc. Cellular device 300 may also includemedium access control layer (MAC) circuitry 304 for controlling accessto the wireless medium and to configure frames or packets forcommunicating over the wireless medium. Cellular device 300 may alsoinclude processing circuitry 306 and memory 308 arranged to configurethe various elements of the cellular device to perform the operationsdescribed herein. The memory 308 may be used to store information forconfiguring the processing circuitry 306 to perform the operations.

In some embodiments, the cellular device 300 may be a UE and be part ofa portable wireless communication device, such as a personal digitalassistant (PDA), a laptop or portable computer with wirelesscommunication capability, a web tablet, a wireless telephone, asmartphone, a wireless headset, a pager, an instant messaging device, adigital camera, an access point, a television, a medical device (e.g., aheart rate monitor, a blood pressure monitor, etc.), or other devicethat may receive and/or transmit information wirelessly. In someembodiments, the cellular device 300 may include one or more of akeyboard, a display, a non-volatile memory port, multiple antennas, agraphics processor, an application processor, speakers, and other mobiledevice elements. The display may be an LCD screen including a touchscreen.

The one or more antennas 301 utilized by the cellular device 300 maycomprise one or more directional or omnidirectional antennas, including,for example, dipole antennas, monopole antennas, patch antennas, loopantennas, microstrip antennas or other types of antennas suitable fortransmission of RF signals. In some embodiments, instead of two or moreantennas, a single antenna with multiple apertures may be used. In theseembodiments, each aperture may be considered a separate antenna. In somemultiple-input multiple-output (MIMO) embodiments, the antennas may beeffectively separated to take advantage of spatial diversity anddifferent channel characteristics that may result between each of theantennas of a receiving station and each of the antennas of atransmitting station. In some MIMO embodiments, the antennas may beseparated by up to 1/10 of a wavelength or more.

Although the cellular device 300 is illustrated as having severalseparate functional elements, one or more of the functional elements maybe combined and may be implemented by combinations ofsoftware-configured elements, such as processing elements includingdigital signal processors (DSPs), and/or other hardware elements. Forexample, some elements may comprise one or more microprocessors, DSPs,application specific integrated circuits (ASICs), radio-frequencyintegrated circuits (RFICs), and combinations of various hardware andlogic circuitry for performing at least the functions described herein.In some embodiments, the functional elements may refer to one or moreprocesses operating on one or more processing elements.

The embodiments described may be implemented in one or a combination ofhardware, firmware and software. Embodiments may also be implemented asinstructions stored on a computer-readable storage medium, which may beread and executed by at least one processor to perform the operationsdescribed herein. A computer-readable storage medium may include anynon-transitory mechanism for storing information in a form readable by amachine (e.g., a computer). For example, a computer-readable storagemedium may include read-only memory (ROM), random-access memory (RAM),magnetic disk storage media, optical storage media, flash-memorydevices, and other storage devices and media. In these embodiments, oneor more processors may be configured with the instructions to performthe operations described herein.

In some embodiments, the processing circuitry 306 may be configured toreceive OFDM communication signals over a multicarrier communicationchannel in accordance with an OFDMA communication technique. The OFDMsignals may comprise a plurality of orthogonal subcarriers. In somebroadband multicarrier embodiments, the cellular device 300 may operateas part of a broadband wireless access (BWA) network communicationnetwork, such as a Worldwide Interoperability for Microwave Access(WiMAX) communication network or a 3rd Generation Partnership Project(3GPP) Universal Terrestrial Radio Access Network (UTRAN) or aLong-Term-Evolution (LTE) communication network or an LTE-Advancedcommunication network or a fifth generation (5G) LTE communicationnetwork or a high speed downlink/uplink access (HSDPA/HSUPA)communication network, although the scope of the invention is notlimited in this respect.

The PHY circuitry 302 may also be configured to transmit and receiveradio frequency electrical signals to communicate directly with one ormore separate wireless devices using a WiFi communication channel of aWiFi communication spectrum. The MAC circuitry 304 may be configured toprepare frames or packets for communicating according to a WiFi standardsuch as an IEEE 802.11 standard for example. The processing circuitry306 may be configured (e.g., by one or a combination of hardware,firmware and software) to initiate transmission of a WiFi subframe viathe WiFi communication channel to reserve communication time on the WiFicommunication channel for use by the same or a different cellular deviceduring the reserved communication time.

FIG. 4 illustrates a simplified example of operating a cellular deviceto reserve time on a WiFi communication channel. The upper part of theFigure shows communication timing windows or time slots for a fourdevice LTE network that includes LTE eNB 404, and LTE UEs 402 a,b,c. Thelower part of the Figure shows communication timing windows for a fourdevice WiFi network that includes WiFi AP 434, and WiFi UEs 432 a,b,c.Time slot 441 and time slot 443 represent communication using the WiFinetwork by WiFi AP 434 and WiFi UE 432 c, respectively. At time slot445, the LTE eNB 404 transmits a WiFi subframe on a WiFi Communicationchannel to reserve time on the WiFi communication channel. The subframemay include a header or may include a message. In response to thesubframe, the WiFi devices defer their transmissions. Box 447 representsan amount of time reserved for communication by the LTE devices usingthe WiFi communication channel. The time slots 449 representcommunications using the WiFi communication channel by the LTE devicesduring the reserved time.

In cellular systems the communications of both the eNB and the UE arescheduled by the eNB. The eNB inherently knows what needs to betransmitted based on its buffers. In some cases, persistent allocations(like reserve time to send a voice packet on uplink every 20 ms) areknown ahead of time by the eNB due to the setup of the dedicated bearer,and the subsequent teardown of the bearer ends the recurringallocations. In other cases, the UE notifies the eNB of its desire totransmit via various bandwidth request mechanisms. The eNB knows whatneeds to be transmitted in the near future, and the eNB may generate amap that is sent to all UEs and the map indicates what portions ofspectrum are used when and by which subscribers for both downlink anduplink communications. The map may communicate the reserved time to a UEand the UE communicates accordingly. Thus, an eNB may not transmit usingthe WiFi communication channel during the time reserved forcommunication by the LTE devices. Although the example of FIG. 4 showsLTE eNB 404 transmitting a message to reserve the communication time,any of the LTE network devices may transmit the message that reservesthe communication time. After expiration of the reserved time (box 447),the WiFi devices communicate using the WiFi network represented by timeslots 451. Box 453 represents a second communication time on the WiFinetwork reserved by the LTE devices.

As explained above, the processing circuitry 306 initiates transmissionof a subframe of a WiFi communication protocol to reserve time on a WiFicommunication channel. FIG. 5 shows a timing diagram of an example of atime reserving message sent by a cellular device. The message includes aWiFi communication protocol header and is followed by one or moresubframes of a cellular network protocol. The header spoofs a physicallayer of a WiFi device to reserve the WiFi communication channel. Theexample in FIG. 5 shows the message including a physical layerconvergence protocol (PLCP) header 561, and the PLCP header is followedby one or more unlicensed LTE downlink (LTE-U DL) subframes 563. ThePLCP header 561 includes a LENGTH and RATE parameter in the signalfield. These parameters can be used to indicate the duration for whichthe WiFi channel is reserved. In an example intended to be illustrative,the RATE parameter may be set to the minimum RATE value to indicatebinary phase shift key (BPSK) modulation and a data rate of 6 megabitsper second (6 Mbps). The LENGTH parameter may be calculated as thedesired duration expressed in seconds divided by the RATE in Mbps andfurther divided by 8 to convert the resulting value from bits to bytes.The result may be rounded up to the next integer value to determine thevalue of the LENGTH parameter. In certain embodiments, the physicallayer spoofing approach can allow reserving the channel forapproximately 5 milliseconds (5 ms) and may allow transmission of up tofive LTE-U DL subframes.

FIG. 6 shows a timing diagram of another example of a time reservingmessage sent by a cellular device. The message takes advantage of theVirtual Carrier Sense feature of a WiFi communication protocol toreserve time on a WiFi communication channel. The Virtual Carrier Senseis a mechanism that includes transmitting an IEE802.11 frame thatincludes a duration field. The duration field contains a value for whichthe WiFi communication channel should be considered busy. Prior tosending cellular communications, a cellular device sends a subframe thatincludes a Request-to-Send (RTS) packet of a WiFi communication protocolor a subframe that includes a Clear-to-Send (CTS) packet (sometimesreferred to as a CTS-to-self packet). The RTS, CTS, or CTS-to-selfpacket 665 includes a duration parameter provided by the MAC layercircuitry. In certain embodiments, the duration parameter is the numberof microseconds (μs) that the channel will be reserved. When the WiFidevices decode the RTS, CTS, or CTS-to-self packet 665 and the durationparameter value, the WiFi devices set their network allocation vector(NAV) accordingly, and the cellular device may send one or more cellulartransmissions 663. The WiFi devices use the NAV to set a counter.Virtual Carrier Sense assumes that the WiFi network is busy while thecounter is nonzero and the WiFi devices will therefore wait for thereserved time. In certain embodiments, this approach may reserve theWiFi communication channel for up to 65 ms, which allows for fullyfunctional LTE frames to be communicated during the reserved time. Afterexpiration of the duration, the WiFi devices return to normal operation.Operation on the WiFi spectrum by a cellular device may be delayed untilthe next WiFi communication channel reservation message.

FIG. 7 shows a timing diagram of another example of a time reservingmessage sent by cellular devices. This approach uses the RTS-CTS packetexchange of the WiFi communication protocol between two devices. A firstcellular device (either a UE or eNB) may send the RTS message. Inresponse to detecting the RTS message, a second cellular device (againeither a UE or eNB) may transmit the CTS message to reserve thecommunication time. The duration parameters of the RTS frame 765 and CTSframe 767 are set to the time to reserve the channel (e.g., expressed inμs).

As for the approach in the example of FIG. 6, the approach in theexample of FIG. 7 may reserve the WiFi communication channel for up to65 ms in certain embodiments. An advantage of the approach in theexample of FIG. 7 is that the complete RTS-CTS exchange results in WiFidevices in the proximity of both cellular devices performing the RTS-CTSexchange deferring their transmissions. In some embodiments, theduration parameter of the WiFi frames in the examples of FIG. 6 and FIG.7 can be set to an arbitrary (e.g., maximum) length to reserve thecommunication channel. A cellular device may transmit a contention freeperiod end (CF-end) frame of the WiFi protocol to end the reservedcommunication time.

The radio frequency (RF) signals involved in a WiFi network aredifferent from the RF signals involved in a cellular network. Forexample, the signal properties may differ in sample rate, subcarrierspacing, etc. It may be necessary to align the WiFi transmission by acellular device to a time slot of the WiFi network. In some embodiments,processing circuitry 306 of FIG. 3 aligns transmission of a WiFisubframe by the cellular device according to a sensed WiFi transmissionby a WiFi device (e.g., he last sensed transmission by a WiFi device).Additionally, the different signal properties between the two types ofnetworks may require the cellular devices to implement complex controlsystems or processing steps to rapidly change the signal properties oftheir communications. In some embodiments, the messages that reservetime on the WiFi communication channel can be pre-recorded. In certainembodiments, the messages can be recorded in the time domain, re-sampledin the frequency supported by the cellular devices, and stored in thecellular devices. A pre-recorded message may then simply be retrievedfrom memory and transmitted by playing it back when it is desired toreserve communication time.

To provide for an acceptable level of performance by both the cellulardevices and the WiFi devices, it may be desirable to promote fairness inthe access to the WiFi spectrum among the devices. One approach topromote fairness is to limit the maximum time that the cellular devicescan reserve WiFi communication time. In some embodiments, a cellulardevice (e.g., the eNB of FIG. 4) reserves communication time of a fixedtime duration. For example, a Virtual Carrier Sense frame may alwaysinclude the same value in the duration field. When the duration expires,there is a fixed waiting period before a cellular device is able toagain transmit a time reserving message. The WiFi device operates usingthe WiFi communication channel during the fixed waiting period. Thevalue of the duration field may be optimized according to the needs of aspecific network. If the duration is too short, the reserving of timemay result in excessive overhead leading to inefficient use of the WiFiand cellular networks. If the duration is too long, the level of qualityof the WiFi network may become unacceptable.

In some embodiments, the periodicity with which a cellular devicereserves communication time changes, but the amount of reserved time isfor a fixed period. In some embodiments, the frequency with whichreserving requests are transmitted may change according to utilizationof the cellular network; with more reserving messages sent when thecellular network experiences high traffic. The one or more antennas 301may be used to sense traffic on the cellular network. The processingcircuitry 306 may initiate transmission of a number of messages toreserve a number of communication time slots on the WiFi communicationchannel, and may adjust the number of reserving messages sent accordingto the determined communication activity on the cellular network. Insome embodiments, the one or more antennas 301 may be used to sensetraffic on the WiFi spectrum and adjust the number of reserving messagessent according to the determined communication activity on the WiFispectrum.

Another approach is to allow the duration time to be a dynamic valuethat changes according to one or both of the traffic in the WiFispectrum and the traffic in the cellular spectrum. In some embodiments,the one or more antennas 301 may be used to sense communication activityon the WiFi communication channel. The processing circuitry 306 mayadjust the value of the duration field (e.g., in one or both of a RTSmessage and a CTS message) according to the sensed communicationactivity. In some embodiments, the processing circuitry 306 adjusts thetransmission time of a message, by moving the transmission earlier orlater. This allows the cellular device to take advantage of a determinedlull in the WiFi network or delay the transmission when the WiFispectrum is experiencing high traffic. In certain embodiments, the WiFicommunication channel is continuously monitored to detect transmissionsby WiFi devices.

The several embodiments discussed have sometimes been described in termsof reserving time on a WiFi communication channel of a WiFi spectrum.The concepts can be expanded to reserve time on multiple WiFicommunication channels. The cellular device 300 may transmit multiplemessages according to a WiFi communication protocol to reservecommunication time on a multiple of WiFi communication channels. Forexample, the processing circuitry may initiate RTS or CTS messages onmultiple WiFi channels and the cellular transmissions may be multiplexedamong the reserved channels.

In some embodiments, a short time duration can be provided during orafter transmission of the Virtual Carrier Sense frame to sense any WiFitransmissions initiated more or less in unison with the Virtual CarrierSense frame. When a WiFi transmission is sensed that overlaps theVirtual Carrier Sense frame a new Virtual Sense frame could betransmitted at the conclusion of the sensed WiFi transmission tore-request the reserving of time on the WiFi communication channel. Thisprovides a way for the cellular device to handle collisions on the WiFicommunication channel.

As explained previously, the network example of FIG. 4 shows a simplecellular network and a simple WiFi network. In actual networks, acellular service provider may co-locate many eNBs. In some embodiments,the transmission of Virtual Carrier Sense frames are synchronized amongthe eNBs to maximize efficient use of the WiFi spectrum by ensuring thatneighboring eNBs are operating in cellular-only or WiFi-only modes. Inthese cases, the duration of the reserve time may have to be extended sothat reservation of WiFi channels can be coordinated with completion ofWiFi transmissions. This extending of the reservation time may also beuseful when multiple eNBs are co-located by different service providers.

The several examples provided describe cellular devices accessingunlicensed radio access network resources in order to increase capacityof the cellular device network. Mechanisms to promote fairness in use ofthe unlicensed resources can promote acceptable quality of service ofboth the cellular network and the unlicensed radio access network.

ADDITIONAL NOTES AND EXAMPLES

Example 1 can include subject matter (such as a wireless cellulardevice) comprising physical layer circuitry configured to transmit andreceive radio frequency electrical signals to communicate directly withone or more separate wireless devices using a communication channel of acellular network and a WiFi communication channel of a WiFicommunication spectrum; and processing circuitry configured to initiatetransmission of a WiFi subframe via the WiFi communication channel toreserve communication time on the WiFi communication channel for use bythe same or a different cellular device during the reservedcommunication time.

In Example 2, the subject matter of Example 1 can optionally include atleast one of a long term evolution (LTE) cellular device, an advancedLTE cellular device, and a fifth generation (5G) LTE cellular device.

In Example 3, the subject matter of one or the combination of Examples1-2 optionally includes processing circuitry configured to initiatetransmission of a clear to send (CTS) packet of a WiFi communicationprotocol to reserve the communication time on the WiFi communicationchannel.

In Example 4, the subject matter of one or any combination of Examples1-3 optionally includes processing circuitry configured to initiatetransmission of a request to send (RTS) packet of a WiFi communicationprotocol to reserve the communication time on the WiFi communicationchannel.

In Example 5, the subject matter of one or any combination of Examples1-4 can optionally include processing circuitry configured to initiatetransmission of a CTS packet of a WiFi communication protocol to reservethe communication time in response to detecting an RTS packet of theWiFi communication protocol transmitted by a separate cellular device.

In Example 6, the subject matter of one or any combination of Examples1-5 can optionally include processing circuitry configured to initiatetransmission of a WiFi communication protocol header to reserve thecommunication time on the WiFi communication channel.

In Example 7, the subject matter of one or any combination of Examples1-6 can optionally include processing circuitry configured to initiate acontention free period end (CF-end) message of a WiFi protocol to endthe reserved communication time.

In Example 8, the subject matter of one or any combination of Examples1-7 can optionally include processing circuitry configured to aligntransmission of a WiFi subframe by the cellular device according to asensed WiFi transmission by a WiFi device.

In Example 9, the subject matter of one or any combination of Examples1-8 can optionally include processing circuitry configured to initiatetransmission of a message according to a WiFi communication protocol,wherein the message includes a duration field to indicate an amount oftime to reserve the WiFi communication channel.

In Example 10, the subject matter of Example 9 can optionally includeone or more antennas electrically connected to the physical layercircuitry and configured to sense communication activity on the WiFicommunication channel, and wherein the processing circuitry isconfigured to adjust a value of the duration field according to thesensed communication activity.

In Example 11, the subject matter of one or any combination of Examples1-10 can optionally include processing circuitry configured to initiatetransmission of a plurality of messages according to a WiFicommunication protocol to reserve communication time on a plurality ofWiFi communication channels.

In Example 12, the subject matter of one or any combination of Examples1-11 can optionally include one or more antennas electrically connectedto the physical layer circuitry and configured to sense communicationactivity on the WiFi communication channel, and wherein the controlleris configured to adjust a transmission time of the WiFi communicationprotocol message according to the sensed communication activity.

In Example 13, the subject matter of one or any combination of Examples1-12 can optionally include one or more antennas electrically connectedto the physical layer circuitry and configured to sense communicationactivity on the cellular network, wherein the processing circuitry isconfigured to initiate transmission of a number of messages to reserve anumber of communication time slots on the WiFi communication channel andto adjust the number of messages according to the determinedcommunication activity on the cellular network.

Example 14 can include subject matter (such as a method, a means forperforming acts, or a machine-readable medium including instructionsthat, when performed by the machine, cause the machine to perform acts),or can optionally be combined with the subject matter of one or anycombination of Examples 1-13 to include such subject matter comprisingtransmitting a WiFi subframe via a WiFi communication channel of a WiFicommunication spectrum using a first cellular device to reservecommunication time on the WiFi communication channel, and communicatinginformation via the WiFi communication channel using the first cellulardevice or a separate cellular device during the reserved communicationtime.

In Example 15, the subject matter of Example 14 can optionally includetransmitting an RTS message of a WiFi communication protocol to reservethe communication time on the WiFi communication channel.

In Example 16, the subject matter of one or the combination of Examples14 and 15 can optionally include transmitting a CTS message of a WiFicommunication protocol to reserve the communication time on the WiFicommunication channel.

In Example 17, the subject matter of one or any combination of Examples14-16 can optionally include a first cellular device transmitting a RTSmessage of the WiFi communication protocol and a second cellular devicetransmitting a CTS message of the WiFi communication protocol to reservethe communication time on the WiFi communication channel.

In Example 18, the subject matter of one or any combination of Examples14-17 can optionally include transmitting a WiFi communication protocolheader to reserve the communication time on the WiFi communicationchannel.

In Example 19, the subject matter of one or any combination of Examples14-18 can optionally include transmitting a CF-end message of a WiFicommunication protocol to terminate the reserved communication time onthe WiFi communication channel.

In Example 20, the subject matter of one or any combination of Examples14-19 can optionally include transmitting a WiFi communication protocolmessage having a duration field to indicate an amount of time to reservethe WiFi communication channel.

In Example 21, the subject matter of one or any combination of Examples14-20 can optionally include sensing communication activity on a WiFinetwork using the first cellular device, and adjusting a value of theduration field according to the sensed communication activity.

In Example 22, the subject matter of one or any combination of Examples14-21 can optionally include sensing communication activity on the WiFinetwork using the first cellular device, and adjusting a transmissiontime of the WiFi subframe according to the sensed communicationactivity.

In Example 23, the subject matter of one or any combination of Examples14-22 can optionally include transmitting a number of WiFi messages viathe WiFi communication channel to reserve a number of communication timeslots on the WiFi communication channel, and wherein the method furtherincludes determining communication activity on the cellular devicenetwork using the at least one of a cellular network node device or a UEdevice, and adjusting the number of WiFi messages according to thedetermined communication activity on the cellular device network.

In Example 24, the subject matter of one or any combination of Examples14-23 can optionally include aligning transmission of a WiFi subframe bythe cellular device according to a sensed WiFi transmission by a WiFidevice.

Example 25 can include subject matter, or can optionally be combinedwith the subject matter of one or any combination of Examples 1-24 toinclude such subject matter, such as a computer readable storage mediumincluding instructions that when performed by hardware processingcircuitry of a wireless communication device cause the wirelesscommunication device to transmit a WiFi subframe via a WiFicommunication channel of a WiFi communication spectrum using a firstcellular device to reserve communication time on the WiFi communicationchannel, and communicate information via the WiFi communication channelusing the first cellular device or a separate cellular device during thereserved communication time.

In Example 26, the subject matter of Example 25 can optionally includeinstructions that when executed by the hardware processing circuitrycause the wireless communication device to transmit at least one of aRTS message or a CTS message of a WiFi communication protocol to reservecommunication time for the cellular device on the WiFi communicationchannel.

In Example 27, the subject matter of one or the combination of Examples25-26 can optionally include instructions that when executed by thehardware processing circuitry cause the wireless communication device totransmit a WiFi communication protocol header to reserve thecommunication time.

In Example 28, the subject matter of one or any combination of Examples25-27 can optionally include instructions that when executed by thehardware processing circuitry cause the wireless communication device totransmit a WiFi communication protocol message having a duration fieldto indicate an amount of time to reserve the communication channel ofthe WiFi communication channel; sense communication activity on a WiFicommunication channel; and adjust a value of the duration fieldaccording to the sensed communication activity.

Example 29 can include subject matter (such as a wireless communicationsystem), or can optionally be combined with the subject matter of one orany combination of Examples 1-28 to include such subject matter,comprising a first cellular device comprising physical layer circuitryconfigured to transmit and receive radio frequency electrical signals tocommunicate directly with one or more separate wireless devices using acommunication channel of a cellular network and a WiFi communicationchannel of a WiFi communication spectrum; one or more antennaselectrically connected to the physical layer circuitry; and processingcircuitry configured to initiate transmission of a WiFi subframe via theWiFi communication channel to reserve communication time on the WiFicommunication channel for use by the same or a different cellular deviceduring the reserved communication time.

In Example 30, the subject matter of Example 29 can optionally includeat least one of a cellular network node device or a cellular UE device.

In Example 31, the subject matter of one or the combination of Examples29-30 can optionally include processing circuitry configured to initiatetransmission of at least one of an RTS packet or a CTS packet of a WiFicommunication protocol to reserve the communication time on the WiFicommunication channel.

In Example 32, the subject matter of one or any combination of Examples29-31 can optionally include a second cellular device, wherein theprocessing circuitry of the first cellular device is configured toinitiate transmission of a CTS packet of a WiFi communication protocolin response to detecting a RTS packet of the WiFi communication protocoltransmitted by the second cellular device.

In Example 33, the subject matter of one or any combination of Examples29-32 can optionally include processing circuitry configured to initiatetransmission of a WiFi communication protocol header to reservecommunication time for the cellular device on the WiFi communicationchannel.

These non-limiting examples can be combined in any permutation orcombination.

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” All publications, patents, and patent documentsreferred to in this document are incorporated by reference herein intheir entirety, as though individually incorporated by reference. In theevent of inconsistent usages between this document and those documentsso incorporated by reference, the usage in the incorporated reference(s)should be considered supplementary to that of this document; forirreconcilable inconsistencies, the usage in this document controls.

Method examples described herein can be machine or computer-implementedat least in part. Some examples can include a computer-readable storagemedium or machine-readable storage medium encoded with instructionsoperable to configure an electronic device to perform methods asdescribed in the above examples. An implementation of such methods caninclude code, such as microcode, assembly language code, a higher-levellanguage code, or the like. Such code can include computer readableinstructions for performing various methods. The code may form portionsof computer program products. The code can be tangibly stored on one ormore volatile, non-transitory, or non-volatile tangiblecomputer-readable media, such as during execution or at other times.Examples of these tangible computer-readable storage media can include,but are not limited to, hard disks, removable magnetic disks, removableoptical disks (e.g., compact disks and digital video disks), magneticcassettes, memory cards or sticks, random access memories (RAMs), readonly memories (ROMs), and the like.

The Abstract is provided to comply with 37 C.F.R. Section 1.72(b)requiring an abstract that will allow the reader to ascertain the natureand gist of the technical disclosure. It is submitted with theunderstanding that it will not be used to limit or interpret the scopeor meaning of the claims. The following claims are hereby incorporatedinto the detailed description, with each claim standing on its own as aseparate embodiment. Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, or process that includes elements in addition to those listedafter such a term in a claim are still deemed to fall within the scopeof that claim. Moreover, in the following claims, the terms “first,”“second,” and “third,” etc. are used merely as labels, and are notintended to impose numerical requirements on their objects.

1-25. (canceled)
 26. A wireless cellular device comprising: physicallayer circuitry configured to transmit and receive radio frequencyelectrical signals to communicate directly with one or more separatewireless devices using a communication channel of a cellular network anda WiFi communication channel of a WiFi communication spectrum; andprocessing circuitry configured to initiate transmission of a WiFisubframe via the WiFi communication channel to reserve communicationtime on the WiFi communication channel for use by the same or adifferent cellular device during the reserved communication time. 27.The cellular device of claim 26, wherein the cellular device includes atleast one of a long term evolution (LTE) cellular device, an advancedLTE cellular device, and a fifth generation (5G) LTE cellular device.28. The cellular device of claim 26, wherein the processing circuitry isconfigured to initiate transmission of a clear to send (CTS) message ofa WiFi communication protocol to reserve the communication time on theWiFi communication channel.
 29. The cellular device of claim 26, whereinthe processing circuitry is configured to initiate transmission of arequest to send (RTS) message of a WiFi communication protocol toreserve the communication time on the WiFi communication channel. 30.The cellular device of claim 26, wherein the processing circuitry isconfigured to initiate transmission of a CTS message of a WiFicommunication protocol to reserve the communication time in response todetecting an RTS message of the WiFi communication protocol transmittedby a separate cellular device.
 31. The cellular device of claim 26,wherein the processing circuitry is configured to initiate transmissionof a WiFi communication protocol header to reserve the communicationtime on the WiFi communication channel.
 32. The cellular device of claim26, wherein the processing circuitry is configured to initiate acontention free period end (CF-end) frame of a WiFi protocol to end thereserved communication time.
 33. The cellular device of claim 26,wherein the processing circuitry is configured to align transmission ofa WiFi subframe by the cellular device according to a sensed WiFitransmission by a WiFi device.
 34. The cellular device of claim 26,wherein the processing circuitry is configured to initiate transmissionof a message according to a WiFi communication protocol, wherein themessage includes a duration field to indicate an amount of time toreserve the WiFi communication channel.
 35. The cellular device of claim34, including one or more antennas electrically connected to thephysical layer circuitry and configured to sense communication activityon the WiFi communication channel, and wherein the processing circuitryis configured to adjust a value of the duration field according to thesensed communication activity.
 36. The cellular device of claim 26,wherein the processing circuitry is configured to initiate transmissionof a plurality of messages according to a WiFi communication protocol toreserve communication time on a plurality of WiFi communicationchannels.
 37. The cellular device of claim 26, including one or moreantennas electrically connected to the physical layer circuitry andconfigured to sense communication activity on the WiFi communicationchannel, and wherein the controller is configured to adjust atransmission time of the WiFi communication protocol message accordingto the sensed communication activity.
 38. The cellular device of claim26, including one or more antennas electrically connected to thephysical layer circuitry and configured to sense communication activityon the cellular network, wherein the processing circuitry is configuredto initiate transmission of a number of messages to reserve a number ofcommunication time slots on the WiFi communication channel and to adjustthe number of messages according to the determined communicationactivity on the cellular network.
 39. A method of operating a wirelesscellular device network, the method comprising: transmitting a WiFisubframe via a WiFi communication channel of a WiFi communicationspectrum using a first cellular device to reserve communication time onthe WiFi communication channel; and communicating information via theWiFi communication channel using the first cellular device or a separatecellular device during the reserved communication time.
 40. The methodof claim 39, wherein transmitting a WiFi subframe includes transmittingan RTS message of a WiFi communication protocol to reserve thecommunication time on the WiFi communication channel.
 41. The method ofclaim 39, wherein transmitting a WiFi subframe includes transmitting aCTS message of a WiFi communication protocol to reserve thecommunication time on the WiFi communication channel.
 42. The method ofclaim 39, wherein transmitting a WiFi subframe includes transmitting aWiFi communication protocol header to reserve the communication time onthe WiFi communication channel.
 43. The method of claim 39, whereintransmitting a WiFi subframe includes transmitting a WiFi communicationprotocol message having a duration field to indicate an amount of timeto reserve the WiFi communication channel.
 44. The method of claim 43,including sensing communication activity on a WiFi network using thefirst cellular device, and adjusting a value of the duration fieldaccording to the sensed communication activity.
 45. A computer readablestorage medium including instructions that when executed by hardwareprocessing circuitry of a wireless cellular device cause the cellulardevice to: transmit a WiFi subframe via a WiFi communication channel ofa WiFi communication spectrum using a first cellular device to reservecommunication time on the WiFi communication channel; and communicateinformation via the WiFi communication channel using the first cellulardevice or a separate cellular device during the reserved communicationtime.
 46. The computer readable storage medium of claim 45, includinginstructions that when executed by the cellular device cause thecellular device to transmit at least one of a WiFi protocol header, aRTS message or a CTS message of a WiFi communication protocol to reservecommunication time for the cellular device on the WiFi communicationchannel.
 47. The computer readable storage medium of claim 45, includinginstructions that when executed by the cellular device cause thecellular device to: transmit a WiFi communication protocol messagehaving a duration field to indicate an amount of time to reserve thecommunication channel of the WiFi communication channel; sensecommunication activity on a WiFi communication channel; and adjust avalue of the duration field according to the sensed communicationactivity.
 48. A wireless communication system comprising: a firstcellular device comprising: physical layer circuitry configured totransmit and receive radio frequency electrical signals to communicatedirectly with one or more separate wireless devices using acommunication channel of a cellular network and a WiFi communicationchannel of a WiFi communication spectrum; one or more antennaselectrically connected to the physical layer circuitry; and processingcircuitry configured to initiate transmission of a WiFi subframe via theWiFi communication channel to reserve communication time on the WiFicommunication channel for use by the same or a different cellular deviceduring the reserved communication time.
 49. The wireless communicationsystem of claim 48, wherein the first cellular device includes at leastone of a cellular network node device or a cellular UE device.
 50. Thewireless communication system of claim 48, wherein the processingcircuitry is configured to initiate transmission of at least one of aWiFi communication protocol header, an RTS packet or a CTS packet of aWiFi communication protocol to reserve the communication time on theWiFi communication channel.